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<title>Untitled Document</title>
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<?php
	$asb = "45" + 45;
	
	echo  "Gia tri 1:" . $asb;
	
	$ari = "45" + 4.5;
	echo "Gia tri 2:" . $ari;
	
	$acb = "45" . 45;
	echo "Gia tri 3" . $acb;
	
	
?>
</body>
</html>